[BUGFIX] TCA: subtypes_addlist not processed

TCA: subtypes_addlist is not processed
if the subtype_value_field is in a palette

Fixes: #30636
Releases: 6.2, 6.1, 6.0, 4.7, 4.5
Change-Id: I6bcaaf36c330962c1d7d9fdd4a73ae502e9710dc
Reviewed-on: https://review.typo3.org/23160
Reviewed-by: Philipp Gampe
Tested-by: Philipp Gampe